
where \(\lbrace \,,\,\rbrace \)  are the Poisson brackets between expectation values defined as \(\lbrace \langle {\hat{f}}\rangle ,\langle {\hat{g}}\rangle \rbrace =\frac{1}{i\hbar }\langle [{\hat{f},\hat{g}}]\rangle \) , \(\hat{f}\)  and \(\hat{g}\)  being arbitrary operators. Moreover, the general expression for the brackets between any two
moments is known [1]}, [2]} to be
\(\lbrace \Delta (\beta ^kp^l),\Delta (\beta ^mp^n)\rbrace =ml\Delta (\beta ^kp^{l-1})\Delta (\beta ^{m-1}p^n)-kn\Delta (\beta ^{k-1}p^{l})\Delta (\beta ^{m}p^{n-1})+\sum _{\begin{array}{c}r=1\\[2pt]\text{odd}\end{array}}^{S}\bigg (\frac{i\hbar }{2}\bigg )^{r-1}K_{klmn}^{r}\Delta (\beta ^{k+m-r}p^{l+n-r}),\) 
